Screen



Dec. lf- 1926.

l 1,610,353. J. BLAND v SCREEN Filed June l. 1925 3 Sheets-Sheet 5 Patented Dec. 14, 1926.

UNITED STATES ro-.EIN BLANIL' or CHICAGO, ILLINOIS. SCREEN( Application led June 1,

' This invention relates to a vibratory screen and particularly'to the vibratory elements by means of which the screen is vibrated. It has for one object to provide an 5 apparatus forl setting up. in a screen an eX- tremely rapid vibration having a wide amplitude. Another object is to provide a spring element for use in connection with a'screen which willserve to give a substaniu tally constant degree of vibration throughout the length of the screen. Other objects will appear from time-'to time throughout the -specication and claims,

My invention is illustrated more or less i diagrammatically in the accompanying drawings, wherein:

Figure l is a side elevation'of the preferred form of screen with parts in section and parts broken away;

zu Figure 2 is a plan view of the screen shown in Figure 1 with parts broken away; Figure l3 is a transverse cross section on enlarged scale taken on line 3 3 of Figure 1; i

Figure 4 is an enlarged longitudinal fragmentary cross section of the end of the screen taken on line 4 4 of Figure 2;

Figure -5 is a plan view with parts broken away showing a modified form of spring mounting;

' Figure 6 is a side elevation with parts broken away and parts in section, showing a modified form of vibratoryelement;

Figure'7 is a side elevation ofone of the spring elements; l

Figure 8 is a plan view of a. modified form of the invention in which the screen' is vibrated at its edges as well as along its i center; 4.0

Figure 9 is a transverse cross section on an enlargedv scale, taken on the-line 9-9 of lFigure 8;

'Figure 10 is a similar cross section taken on line 10-10 of Figure 8.

Like parts are indicated by like characters throughout. v

A is a foundation or bottom member for a screen. A? A1 are uprights which support the screen from the foundation member A. A2 A2 are side frame `members of the screen. They are provided with inwardly extending anges A8 at their upper edges, and similarfianges A4 at theirlower' edges. lThey are provided intermediate 55 their lower and upper edges with inwardly extending angle members Als A5 to which 1,610,353 4ENT oFFIcE.-

1925. Serial No. 33,876.

'screen cloth sections A A are fastened.

The-edges ofthe screen cloth sections are held down to the flanges .Ali by means of retaining strips A". They may be bolted or riveted Iin the position shown particularly in Figure 3. A8 is the end member 'of the frame similar to the side members and provided with an upper flange A9 and a lower flange A1", and intermediate flanges Isimilar to the flanges A5 ofl the side sections to which the ends of the screen cloth are fastened.

The lower end of the screen frame is open to permit discharge of the material which runs off the screen. It is provided with one or more fiat members A11 which serve to support the screen cloth sect-ions and join the side members. Alg is a bottom plate fastened to the screen frame, preferably to the lower flanges of the side and end frame members.`

B is a spring member. It is mounted between the upper and lower screening surfaces. It is preferably made of wood, although it might be made of other material. It is preferably provided with a pair of generally triangular slots B1 B2 cut through it and having their wide ends near the ends of the spring member and their lnarrow or pointed vends extending toward each other and toward the solid portion B'.

Above the solid portionl B3 is preferably mounted inthe form shown specifically in Figures 1, 2 and 3, the block 0.1 `Upon this is mounted al bearing C1 which carries one end of a shaft C2, the other end of which is mounted in a bearing C3 Iand pivotally supported 'between the members U4. The outer end of the shaft carries a driving. pulley C*s by means of which it is rotated about a belt C by a motor C7- or any other suitable power1 source. Mounted on the shaft C2 is one or more outfof-bala-nce fly wheels C8 C".

D' is a feed ho per into which material is fed and-from t e bottom of which it is discharged upon the upper surface ofthe screen. It is provided with an adjustable valve plate D1 which may be movedup or down with relation to the hopper to vary the space betweenv its lower vedge and thel upper surface of thel screen and thereby'to vary the thickness of the sheet of material 'which can be discharged upon the upper .ture generally.

'or both ends, and Figure 5 is intended to illustrate this form. Only one endis shown because the other end, if left'f-ree, is the same as the end shown in Figure 5.

As shown in Figure 6 the vibratory element' is of a different design. Instead of mounting the out-of-balance shaft directly on the spring member B at the solid portion B3, it is mounted upon a vertical member sprin E. Thus a spring member E is provi ed which is fixed at its lower endvupon a part of the foundation A, At its upper end it is fastened to the spring B beneath the solid parts B3 upon which is mounted in suitable bearings a shaft E1 which carries one or more outofbalance fly wheels E2 and a driving, pulley E2, through which by means of a belt E4 the shaft may be rotated from amotor E5 or .any other suitable power source.

In Figures 8, 9, and 10 a further modified form is shown. As shown in this form there is provided a pair of side spring frame members F F. .The screen sections F1L F2 are mounted above and below these side members.

Running between the screen sections and generally parallel to the side members F is a spring member G which is the same as the spring member B shown in the earlier figures and describedin connection with them.

"their upper ends carry the framework and at their lower ends are fastened -to a foundation `or any other suitable support. The screen is open at its lower en'd to permit discharge of material.

.I is a bearing mounted upon the spring G yand carrying a shaft' I1 which carries one or more out-o-fbalanc'e rotors I2.

J J are bearings mounted one upon each of the side members F, carrying respectively shafts J2 J 3, each of said shafts being joined at its inner end tothe shaft'I1L by a flexible joint J. Each of said`shafts`carries adjacent its outer end an out-of-balance rotor J 5. The shaft J2 carries in addition at its outer' end a driving pulley J 6 which is rotated by a belt J 7 from any suitable power source. v

At their ends the side frame members F are joined and held in proper spaced relation by means of tie rods K; Each of the tie rods passes through the side spring members F, the central spring member G and the frame supporting members H1. Each of said tie rods is provided adjacent its outer end with a rubber orother flexible bushing K1, and through each of said' bushings it is provided with nuts K2. These nuts are screwed toward each other andthe rubber bushings are thereby placed under compression and bulge out slightly at their endsand adjacent their centers as is shown, and thereby properly place the spring elements F with relation to the'supporting members y'H1 and prevent lateral displacement or movement of these parts. Surrounding the tie rods at the points where they pass.

through the spring member AGr and engaging that spring member are additional rubber bushings K8. These serve` generally the 'same purpose described with respect to the outer bushings.

There is provided for the screen in the first two formsa discharge receiving chute. Q L, one chute being provided for each of the screen decks and one for the fines that pass through the lower deck. Thus three chutes are provided in all.

No such arrangement is shown for the screens illustrated in Figures 8, 9, and 10 but any suitable .discharge receiving arrangement may be provided in connection with that form of the invention, and a bottom platey similar to the plate A12 may also be provided below the lower screen F1 or any other means provided for receiving material which passes through the lowest screen. i

u Although I- have shown an operative device, still it will be obvious that many changes Vmight be made in size, shape and arrangement of parts ywithout departing materially from the spirit of my invention; and I wish, therefore, that my showing be takenas in a sense diagrammatic.

Theuse and operation of my invention are as follows:

In the form shown in Figures 1 to 5 in-y clusive, the parts are assembled in the position shown. The rotary element is set in rotation and because of its outof-balance it sets up a vibration. Since the rotary element is mounted sov as to act upon the central longitudinal spring B, when it is in vibration it sets up a vibration along this member, usually.l setting it in vibration in a wave-like motion. This sets up vibration lill) llt) and vibrates the two screen decks attached to the spring member.

4Material to'be screened is fed upon the upper deck and the screening operationv One of the important features of this form of the invention is that the screen cloth itself is directly attached to the vibrating spring element, and thus the vibration is transmitted directly from this spring element to the screen cloth.

The action of the longitudinal' sprin member B is generally the same Whether or not it be attachedv to the frame at one end or both ends. In either case a wavev like vibration is set up in it and this vibration is transmitted directly to the screen cloth Which is attached to this spring element.

In the form shown in Figure 6 the vibratory element instead of being mounted so as to act directly upon the longitudinal spring element is mounted upon a vertical spring'I element. This element is fixed at its bottom end and at its top is attached to the longitudinal spring element B. Rotation of the out-of-balance rotor causes lateral bendillig movement of the vertical spring member As this member is bent laterally, and since it is held against pivotal movement at its ends, its vertical height is shortened. This periodical shortening of the vertical spring member due to rotation of the out-of-balance rotor sets up vertical movement at the upper end of the spring member. This being attached to the longitudinal spring member B imparts to it a vibratory movement and it is thus vibrated.

.In the form shown in Figures 8, 9, and 10 the central longitudinal spring member is generally the s ame as that shown in the other figures. In addition to this, however, s ideplongitudinal spring members are pro. vided. These may o r may not be ofthe same construction but they are essentially spring members. The screen cloth is directly attached above and below thesethree longitudinal spring members. Each of these carries a bearing which supports one or more out-of-balance rotors.- When these are rotated a vibration is imparted to the longitudinal spring members, in this case the members Gand F, and a wave-like vibration is set up along eachof them. Thus 'the screen cloth which is attached to each of them is set into vibration.

The feed of material upon thepforms of screen shown in Figures 6 to 10 inclusive is generally the same as that described above in connection with the other figures. It will be noted that all of the ,forms of the invention have in common the feature of a longitudinalspring member which is atl tachedto the screencloth and which is vibrated, and this imparts vibration directly to the cloth.

The stiffness of the spring member' is preferably varied throughout its length so as to provide an equal degree of vibration throughout its length. For some purposes.

this might not be the case, but it is usually preferable so to vibrate the spring member B that the degree of vibration imparted from it to the screen cloth is substantially. the same throughout the length of the screen.

I claim: 1. In a screen, a screening member and a plurality of separated spring `members each attached to said screen member throughout its length, and means for vibrating said spring members including an out-of-balance rotor adapted to act directly upon said spring members.

2. In a screen, ascreening member, and a spring member attached to said lscreening member throughout its length and means for vibrating said spring member, said spring member being of varying flexibility throughout its length so that it is flexed substantially equally throughout its length.

3. In a screen, .a screening member and a plurality of spring)- members each attached to said screen member throughout its length, and means for vibrating said spring members, said spring members being of varying flexibility throughout their length so that they are flexed substantially equally throughout their length.

4. In a screen, a screening member and a plurality of spring members each attached to said screen member throughout its length, and means for Vibrating said spring members including an' out-of-balance rotor adapted to act directly upon said spring members, said spring members. being o varying flexibility throughout their length so that they are flexed substantially equally throughout their length.

5. In a screen, a screening member and a frame for said member formed of members adapted to be fiexed, in combination with a spring member adapted to be attached to said screen member throughout its length and means for vibrating said. frame'and said spring member, said meansincluding an out-of-balance rotor.

7. In a screen, a screening member'anda frame for said member formed of members adaptedto be flexed, in combination with a spring member adapted to be attached to said screen member. throughout its length and means for vibrating said frame and said spring member, the flexibility of said spring member being varied throughout its length so' that it is flexed substantially equally throughout its length.

8. In a screen, a screening member and a frame for said member formed of members adapted to be flexed, in combination with ya spring member adapted to be attached 4to said screen member throughout .its length and means for' vibrating said frame and said spring member, said-means including an outof-balance rotor, the flexibility of said spring member being varied throughout its length so thatvit is flexed substantially equally throughout its length. l

9. In a screen, a plurality, of levels of screen cloth, a plurality of spring members attached to each of said levels of screen cloth,

and means for vibrating said spring members including an out-of-balance rotor adapted to act upon each of such springs, the flexibility of such springs being varied throughout their length so that each of them is flexed substantially equally throughout its length.

screening member .and a 10. In combination With a screen having a frame for such member from which the same is supported,

a self sustaining resilient vibrating member extending from end to end of the screen' and secured to it and means for Vibrating such resilient member, including an out of balance otor adapted to act directly upon such mem- 11. ln combination with a screen, a plurality of screen members and a frame for such members. from which they are supported, a plurality of flexible vibratory members of substantial Vertical thickness interposed between such screens, the upper screen positively secured `to the upper surface of such vibratory member and the lower screen secured to the lower surface of such member along substantially the entire length of such screens, means for vibrating such flexible members including a vibratory member adapted to act directly upon such flexible member.

Signed at Chicago` county of Cook and State of Illinois, this 27th day of May, 1925.

JOHN BLAND. 

